Electromagnetically managed latching exit bar

ABSTRACT

An exit bar for securing a door has a housing adapted for mounting to a door. A push pad for receiving a push force is mounted to the housing. A latch extends from the housing to releasably latch the door to which the exit bar is mounted. A link system links the push pad to the latch so that a push force exerted on the push pad releases the latch. An electromagnetic lock disposed in the housing locks the link system to prevent releasing of the latch. The electromagnetic lock employs an electromagnet and a movable armature to lock the link system. The exit bar further delays unlocking the link system for a preestablished delay time after the push pad has been pushed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is the national stage of International Application No.PCT/US96/13709 filed Aug. 23, 1996, and is a continuation-in-part ofU.S. application Ser. No. 08/518,759 filed Aug. 24, 1995--now U.S. Pat.No. 5,823,582.

BACKGROUND OF THE INVENTION

This invention relates to the field of door security systems. Morespecifically, this invention relates to the use of a push or exit barfor securing a doorway.

Push bars or exit bars which allow egress through a doorway whilelimiting ingress are well-known components of door security andemergency systems. The conventional exit bar is mounted on the interiorside of the door to be secured and is oriented generally horizontallyacross the face of the door. A push force on the bar toward the doorface operates a door latch to permit opening of the door. Conventionalexit bars typically employ a mechanical linkage to actuate the latchmechanism for unlatching the door. Exit bars may also employ mechanicallocks to secure the door from opening. A handle can be additionallyprovided on the exterior face of the door to allow ingress under certaincircumstances. Exit bars have also been connected with alarm systems towarn security personnel of a door opening.

Conventional exit bar systems while enjoying great popularity have alsoexhibited a number of deficiencies. For example, to secure an exit barfrom operating the associated latch may require individually manuallylocking each bar. For most applications, it is generally undesirable forsafety reasons to permanently lock exit bars. Even when a building haslow occupancy, there may be times when for emergency reasons, exit doorsshould not be secured in a permanent fashion that would inhibit egress.

During periods of high traffic levels through a doorway, mechanicallatch mechanisms of a conventional exit bar can experience a high rateof wear. To reduce wear on mechanical latch components, someconventional exit bars may be manually locked in a dogged positionwherein the latches remain in a retracted state. However, each bar mustbe directly manually dogged and undogged at the site of the door.

Similar problems arise with regard to exit bar systems that employ anauxiliary outside handle to allow selective ingress to a secured area.The operative mode of these outside handles must be generallyindividually manually changed by visiting the exit bar installation toset the desired mode.

In more advanced systems, alarms have been connected to exit bars togenerate audible or visible indications when an egress is attempted.These alarms are generally not sophisticated in distinguishing betweenpermitted and unpermitted egresses. In health care facilities, alarmsmay also be used to indicate attempts by patients to egress thefacility. Such alarms are particularly important in facilities wherepatients may need monitoring or assistance in egressing. For example, infacilities caring for patients lacking full mental or physicalcompetence, such as nursing homes or child care facilities, egress forsome individuals should be prevented in other than emergency situations.However, a deficiency of many conventional exit bars is to allowimmediate egress even when the exit bar is combined with an alarm. Thismay permit unauthorized personnel or patients to immediately exit asecured area.

Attempts have been made to combine exit bars with various forms of doorlocking and security systems to overcome some of the above-mentionedproblems. Such hybrid systems, however, tend to result in excessivecosts and complexity. Such combination lock systems may require mountingnot only the exit bar, but also mounting an auxiliary lock system to thesecured door.

Exit bars further can exhibit a deficiency common to many electroniclock systems. Typically, a large number of wires are required to beinstalled across the hinge connecting the door and door frame in orderto provide a large number of functions for the exit bar. A singlefunction may require two or three individual wires. The electricalconnections across the hinge often necessitate special hardware andcable covers to hold the wires. These special materials can increaseinstallation costs and reduce operating reliability.

SUMMARY OF THE INVENTION

Briefly stated, the invention in a preferred form is anelectromagnetically secured exit bar for mounting to a door. The exitbar employs a mechanically actuated latch. The latch may be unlatched bya force applied to a push pad on the front of the exit bar. Locatedwithin the exit bar is a selectively, electrically actuated lockingmechanism. The locking mechanism employs an electromagnet and a moveablearmature to lock the exit bar latch and therefore secure the door.

In a preferred form of the invention, the mounting structure for theelectromagnet armature is configured in such a manner as to allow aninitial limited movement of the push pad before unlatching the door.This initial movement triggers an electric switch mechanism to initiatean alarm, implement instantaneous unlocking from inside, begin a delayedunlocking sequence or initiate other security measures. In one preferredform, a delay unlocking sequence commences at the time of initialcontact on the push pad. At the end of a preestablished delay period,the exit bar unlocks thereby allowing further displacement of the pushpad to unlatch the door. The preestablished delay period in unlockingthe exit bar allows time for security personnel to arrive at the site ofthe door or otherwise respond if required to assist or prevent egress.

The electromagnetically secured exit bar further provides selective,permanent unlatching, or dogging, of the latch mechanism during times ofhigh traffic use of a doorway. The dogging of the latch mechanism can bepreferably initiated from a remote location. The exit bar is signalledto prepare to dog the latch. The actuation of the exit bar by the nextdoor user results in dogging of the latch mechanism. Therefore, nosecurity personnel are required to access the site of the exit bar inorder to initiate and complete the dogging of the exit bar. The doggingof the latch mechanism allows the door to be transformed to a push-pullmode for free ingress and egress. In addition, the user's hands are freefor other tasks. The dogging may also reduce wear on the lock mechanismdue to repetitive latching and unlatching, and also speeds the user'spassage through the door.

In locations where ingress through the doorway is desired, a handle maybe provided at the exterior side of the door. A fixed handle may beemployed to allow ingress for applications where the exit bar is dogged.The handle may also be configured to actuate the latch through anunlocking mechanism similar to that employed in conjunction with thepush pad. The unlocking mechanism secures the door from immediateaccess, which can be granted by electrical access control systems like akeyswitch or more sophisticated systems which employ card readers,keypads, touch keys, etc.

The exit bar may be further integrated into an overall security systememploying readers, touch pads, electronic keys or other personnelidentification security measures. Such security systems readilyinterface with the electromagnetic lock system to control both ingressand egress through the door. For example, a reader could be provided atthe exterior side of the door. The exit bar of the invention could becontrolled so as not to allow ingress until a valid code has beenentered into the reader. In one preferred form, the exit bar comprises alock control system and multiple electronic access devices or accesscode readers at the exterior and/or interior of the door. One of thereaders is preferably a key pad for receiving personal access codes. Asecond reader is an electronic "key" reader, such as a card reader, acontact activatable reader port and/or a computer data port which alsoreceives an electronic personal access code. The lock control system ofthe exit bar is responsive to either entry of a personal access code atthe key pad or contact by an electronic "key" at the electronic reader.The exit bar could be further controlled to allow immediate egresswithout delay when the valid code is entered into a reader at theinterior side of the door. An attempted egress without use of a validcode would initiate the delayed unlocking system and actuate an alarm.The exit bar is preferably programmable to define a plurality ofpossible operating parameters which are specifically selected for agiven application.

The exit bar can be further configured to provide an electronic recordor audit trail to record the passage of identified individuals throughthe door secured by the exit bar. A lock control system of the exit barcan store access codes that will allow actuation of the lock. The accesscodes can be entered by use of the reader. The user access number andtime and date of the use of the exit bar are then stored by the lockcontrol system. The lock control system can preferably also store otherlock events such as fire alarm activations, invalid access code entries,etc. The lock control system records the time and date of each eventthat occurs for downloading at a later time by a remote security systemor a portable programming and retrieval device.

Furthermore, the invention may be combined with other alarms at thelocation of the door or at a remote location to signify attempted egressor ingress. In another preferred form of the invention, the exit bar ofthe invention may be placed in various latched, unlatched, locked andunlocked modes from a remote location such as a central securityconsole. The exit bar of the invention can also be efficientlyintegrated into a fire alarm system. The exit bar for such anapplication provides an important fail safe feature. Should power beinterrupted during an emergency situation, the locking electromagnetreleases allowing immediate egress and ingress through the doorway. Ifthe exit bar is in the dogged mode when power is interrupted, the exitbar returns to the undogged latched state.

In a further embodiment, a communication system in accordance with theinvention can control a plurality of exit bars in unison. Thecommunication system preferably operates a pair or bank of doors as asingle opening resulting in reduced complexity and increased safety. Thecommunication system can also be employed with a single exit bar. Thecommunication system requires a reduced amount of wiring for each exitbar, resulting in decreased installation costs and increasedreliability. In one embodiment, only four conductors or wires arerequired to power and control the plurality of exit bars.

An object of the invention is to provide a new and improved exit barthat may be efficiently and reliably controlled from a remote location.

Another object of the invention is to provide an exit bar having adelayed unlocking system to allow security or hospital personnel time torespond to the site of the secured door.

A yet another object of the invention is to provide an exit bar capableof multiple optional operating modes.

A further object of the invention is to provide an exit bar that may beeasily and efficiently employed in conjunction with other security orfire alarm systems.

A yet further object of the invention is to provide an exit bar that canbe efficiently dogged in an unlatched position during times of highusage.

A still further object of the invention is to provide a communicationnetwork to control a plurality of exit bars.

Other objects and advantages of the invention will become apparent fromthe drawings and the specification.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top longitudinal sectional view, partially broken away,partially in schematic, and partially in phantom, of a preferredembodiment of the exit bar of the invention illustrated in conjunctionwith a door and door latch;

FIG. 2 is a diagonal sectional view of the exit bar of FIG. 1 takenalong the line 2--2 thereof;

FIG. 3 is a cross sectional view, partially broken away, of the exit barof FIG. 1 taken along the line 3--3 thereof;

FIG. 4 is a cross sectional view of the exit bar of FIG. 1 taken alongthe line 4--4 thereof;

FIG. 5 is a fragmentary longitudinal sectional view, partially inphantom, of the exit bar of FIG. 1 taken along the line 5--5 thereof;

FIG. 6 is a fragmentary cross sectional view, partially broken away, ofthe exit bar of FIG. 1 taken along the line 6--6 thereof;

FIG. 7 is a cross sectional view of the exit bar of FIG. 1 taken alongthe line 7--7 thereof;

FIG. 8 is a top longitudinal sectional view, partially broken away andpartially in phantom, of the preferred embodiment of the exit bar ofFIG. 1 at a second operative position, illustrated in conjunction with adoor and door latch;

FIG. 9 is a top longitudinal sectional view, partially broken away andpartially in phantom of a shear magnet embodiment of the invention,illustrated in conjunction with a door and a door latch;

FIG. 10 is a fragmentary diagonal sectional view of the exit bar of FIG.9 taken along the line 10--10 thereof;

FIG. 11 is a cross sectional view, partially broken away, of the exitbar of FIG. 9 taken along the line 11--11 thereof;

FIG. 12 is a cross sectional view of the exit bar of FIG. 9 taken alongthe line 12--12 thereof;

FIG. 13 is a fragmentary longitudinal sectional view, partiallybroken-away and partially in phantom, of the exit bar of FIG. 9 takenalong the line 13--13 thereof;

FIG. 14 is a fragmentary cross sectional view, partially broken-away andpartially in phantom, of the exit bar of FIG. 10 taken along the line14--14 thereof;

FIG. 15 is a top longitudinal sectional view partially broken away andpartially in phantom, of the shear lock embodiment of the inventionpartially engaged and illustrated in conjunction with a door and doorlatch;

FIG. 16 is a schematic view of an alternative configuration of thepreferred embodiment of the invention mounted to the door andillustrating various auxiliary features thereof;

FIG. 17 is a simplified schematic block diagram of the lock controlsystem for the exit bar of FIG. 1;

FIG. 18 is a simplified schematic diagram of a communication systemhaving a communication controller and a plurality of exit bars of FIG.1;

FIG. 19 is a simplified schematic electrical diagram of thecommunication controller of FIG. 18; and

FIG. 20 is a flow chart for the polling routine of the communicationcontroller of FIG. 19.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the drawings, wherein like numerals represent likecomponents or structures throughout the Figures, a locking pole magnetexit bar of the invention is generally represented by the numeral 10(see FIGS. 1-8 and 16). The exit bar 10 is mounted in a horizontalposition across the interior side of a door 14 to be secured. The exitbar 10 latches against a strike mounted to the door frame from which thedoor 14 is supported. A push force applied at the front of the exit bar10 retracts the latch from the strike and releases the door to open foregress. Power is supplied to the exit bar from a remote power source.The exit bar 10 is adapted to provide multiple locking, unlocking,latching and unlatching or releasing functions, and to interface withvarious security and alarm systems as will be detailed below.

The exit bar 10 has an elongated main housing 12 which provides theprincipal mounting and support structure. The length of the housing 12is preferably sufficiently long to substantially span the width of thedoor 14. The main housing 12 is mounted to the door 14 by screws orother fasteners (not shown) which secure the back panel 15 of thehousing in surface to surface disposition at the interior (secured) sideof the door. The main housing 12 is channel-shaped with an elongatedopening of the channel being spaced away from the door 14. Atransversely displaceable push bar or pad 30 is located in the channelopening. The push pad defines a push face for receiving a push forceexerted toward the door 14 by a person attempting to egress through thedoor. The push pad 30 longitudinally spans a substantial portion of thehousing 12 with the housing terminating in a latch housing 18 and anopposite end enclosure 19 which is generally tubular with a rectangularcross section.

Fixed inside the main housing 12 is a main lock frame 16. The main frame16 is also generally channel-shaped to define an opening which is alsospaced away from the door. The main frame 16 is fixed to the back panel15 of the housing 12 by screws or other mounting hardware. For purposesof describing the invention as viewed in the plane of FIG. 3, thehousing 12 defines a central longitudinal axis which extends parallel tothe panel 15 and a transverse axis which extends perpendicularly fromthe panel surface.

The exit bar 10 secures the door 14 by use of a retractable orreleasable latch 20 which is pivotally mounted in the latch housing 18.Latch 20 is held in a normally extended or latched position by a latchspring 22. The latch spring urges the latch 20 to a first positionagainst strike 24 mounted to the door frame 26. A latch cover 28surrounds latch housing 18 to keep contaminants from the latch 20. Whenpush pad 30 is transversely pushed into the housing 12 by a personattempting to egress, a retraction lever drive pad 56 mounted to thepush pad 30 contacts a pivotally mounted latch retraction lever 58. Theretraction lever drive pad 56 pivots latch retraction lever 58 whichcontacts latch 20 to pivot latch 20 to a second released or unlatchedposition whereby the door 14 may be opened.

A push force applied to the push pad 30 is transferred through a seriesof links and pivots to move an armature 70 in relation to anelectromagnet 64. The transverse motion of the push pad 30 isessentially translated by the links and pivots into a motion where thearmature 70 swings in an arc from a position in full contact with theelectromagnet 64 to a position in only partial contact with theelectromagnet 64 to thereby provide various latching or locking modes aswill be described below.

Push pad 30 is pivotally linked to the frame 16 for limited transversemovement therewith by a master main link 32 and a slave main link 34.The master main link 32 and slave main link 34 are pivotally connectedto the push pad 30 by pins 36, 38. A master main link pin 40 extendsthrough the master main link 32 and slidably engages in master main linkpin slots 42 formed by the frame 16. In a similar construction, a slavemain link pin 44 extends through the slave main link 34 and slidablyengages in slave main link pin slots 46 formed by the frame 16. Themaster main link pin slots 42 and slave main link pin slots 46 aregenerally perpendicular to the face of the door 14 upon installation ofthe exit bar 10.

As viewed in FIG. 1, master main link 42 extends from the push pad 30 toalmost the bottom of the channel of the frame 16. A second link pin 48extends through master main link 32 and slidably engages into mastermain link lower slots 50 formed by frame 16. Slave main link 34 alsoextends to near the bottom of the channel of frame 16. A second slavemain link pin 52 extends through the slave main link 34 and slidablyengages in slave lower slots 54 formed by frame 16. The correspondinglower guide slots 54, 50 are oriented generally parallel to the face ofthe door 14 in the longitudinal direction. The construction of themaster main link 32 and slave main link 34 with the associated actuationof pins and slots defines a transverse path for the push pad 30. Uponapplication of a push force, the transverse motion of the push pad istranslated into a generally longitudinal motion at the bottoms of themaster main link and slave main link due to the orientation of the lowerguide slots 50, 54.

A slot 60 extends partially through master main link 32. (See FIG. 2.) Adrive link 62 is located in slot 60 and pivotally connected to mastermain link 32 by link pin 48. Drive link 62 extends longitudinallyparallel to the door face toward the end of the housing 12 opposite thelatch end.

The links 32, 34, pins 36, 38, 40, 44, 48, 52, slots 42, 46, 50, 54,retraction pad 56 and lever 58 all act in concert as part of a linksystem to allow the push pad 30 to retract latch 20.

Within the exit bar 10, an electromagnet 64 serves to lock the bar (andhence the latch 20) by at least partially limiting the motion of thelink system, and therefore preventing the push pad 30 from retractingthe latch 20. The elongated E-shaped electromagnet 64 is fixedly mountedto the back panel 15 of the housing 12 and positioned to extend throughan opening in the bottom of the frame 16 (as viewed in FIGS. 1-8). Theelectromagnet 64 is arranged longitudinally with the long axis of theelectromagnet parallel to the long axis of the housing 12 and frame 16.The electromagnet 64 is preferably constructed of a series of stackedE-shaped plates 66 which act as poles of the electromagnet. Anelectromagnet coil 68 is positioned in the slots defined by the stack ofE-shaped plates 66. The rectangular ends of the legs of the stack ofplates 66 define an attractive magnetic face 72.

With reference to FIGS. 1 and 8, the armature 70 and electromagnet 64magnetically bond to lock the link system to prevent the push pad 30from moving transversely a sufficient distance that would allow thelatch 20 to be retracted.

An armature 70 is located so as to have surface to surface contact withthe attractive face 72 of the electromagnet 64 when the bar 10 is in alocked state. The armature 70 is constructed of a ferromagnetic materialto provide a strong bond between the electromagnet 64 and the armature70 when the electromagnet 64 is energized. The armature 70 is mounted toan armature tray 74 by an armature suspension bolt 76 to be describedlater. The armature tray 74 is moveable from a position wherein thearmature 70 is in full contact with the attractive face 72 of theelectromagnet 64 to another position 74a (See FIG. 1) wherein thearmature is in only partial contact with the attractive face 72 of theelectromagnet 64.

The movement of the armature tray 74 is accomplished by use of a masterauxiliary link 78 pivotally connected to drive link 62. Master auxiliarylink 78 is pivotally connected at the first end to drive link 62 and atthe second end to armature tray 74 by pins 80, 82, respectively. Masterauxiliary link 78 pivots about a permanently positioned pivot pin 84mounted to the frame 16. The armature tray is supported at the secondend by a slave auxiliary link 86. Slave auxiliary link 86 is pivotallyconnected to armature tray 74 by pin 88. Slave auxiliary link 86 pivotson a permanently positioned pivot pin 90 also mounted to the frame 16.

The coordinated interaction of the link system results in the preciselymanaged swinging of the armature tray 74 and armature 70. Pressure onpush pad 30 drives master main link 32 transversely toward the door 14.Pin 40 slides in slots 42 and pin 48 slides in slots 50 to allow themaster main link to move to a second position 32a. Slave main link 34slides in the respective slots to result in the same synchronizedmotion. Consistent and smooth transverse motion of the push pad 30 isaided by tie links 92 extending longitudinally from and connectingtogether pin 48 to pin 52. The tie links 92 (FIGS. 2 and 3) are locatedon either side of the frame 16.

The movement of master main link 32 to position 32b pushes drive link 62toward the end of the housing opposite the latch end. This causes masterauxiliary link 78 to pivot on pin 84 to a second master auxiliary linkposition 78b. The pivoting of master auxiliary link 78 lifts armaturetray 74 away from the electromagnet 64. The lifting of the armature tray74 from the electromagnet 64 also causes slave auxiliary link 86 topivot. Master auxiliary link 78 pivots to a second position 74b andslave auxiliary link pivots to a second position 86b when push pad 30receives a push force. The armature 70 is moved in an arcuate pathbecause of the parallelogram-like structure of the auxiliary links 78,86, to a position 70b wherein only a portion of the armature is incontact with attractive face 72 of electromagnet 64.

The employment of an electromagnet 64 for the locking function providesa reliable manner of securing the exit bar 10 with a high degree ofbonding integrity. The electromagnet 64 generates a strong attractiveforce on the armature 70 to bond the armature to electromagnetattractive face 72. Transversely pulling the armature from the energizedelectromagnet requires a greater force than sliding the armaturelongitudinally (shearing the armature from the electromagnet). Thearrangement of the links and the armature tray to effect a lifting ofthe armature away from the attractive face 72 of the electromagnettherefore exploits an optimum bonding configuration. This configurationis referred to herein as the pole magnet arrangement.

An auxiliary handle 94 may also be provided to allow unlatching thelatch 20 from the second or exterior side of the door 14. The auxiliaryhandle 94 located on the second side operates a spindle 96 extendingthrough the door 14 to rotate a cam 98. (See FIGS. 1 and 5.) The cam 98contacts the end of drive link 62 to drive the drive link when thehandle 94 and spindle 96 are rotated. The armature tray 74 is thereforeactuated to move in the same manner as when push pad 30 receives apushing force and actuates movement of the armature tray 74. The cam 98is maintained in place by use of a cam cover 100. A "torsion" coilspring 102 acts against a post 104 on the cam and a post 105 on the camcover to maintain the handle 94 in a first position. Rotation of thehandle 94 causes the lobe of the cam 98 to act on the drive link 62 andmove the drive link 62 toward the end of the housing opposite the latchend. The motion of the drive link 62 by the cam 98 causes the mainmaster link 32 and, through the communication provided by tie links 92,slave master link 34 to slide longitudinally and draw the push pad 30transversely toward the door 14. Drawing the push pad 30 inward resultsin actuation of the latch 20.

Push pad 30 is maintained in an extended position away from the door 14and the links are maintained in an initial position by the bias of amain spring 106. One end of the main spring 106 acts against an anchorblock 108, and the second end acts against the slave main link 34.Because of the arrangement of the described pivotal link system, themain spring 106 maintains the armature 70 in full surface to surfacecontact with the attractive face 72 of the electromagnet 84, even whenthe electromagnet 64 is not energized.

A suitable opening force applied to the push pad 30 or handle 94activates an initial motion switch 112 to initiate the alarm and delayfeatures of the invention. Coaxially located inside of main spring 106is a main spring carrier 110. Main spring carrier 110 is pivotallyaffixed to pin 52 and extends through the anchor block 108 toward theend of the housing (right as viewed in FIG. 1). The end of the mainspring carrier is beveled to contact the microswitch 112 along a switcharm 114.

When push pad 30 is pushed or handle 94 is rotated through the linkagespreviously described, main spring carrier 110 is forced outward in thelongitudinal direction toward the end of the housing opposite the latchend. This longitudinal motion causes switch arm 114 to ride on thebeveled end of spring carrier 110 and therefore to activate switch 112.

Switch 112 is electrically connected via lines 116 to the lock controlsystem 118. Activation of switch 112 generates a signal to the lockcontrol system 118. The lock control system 118, which may assume a widerange of structures and provide for numerous optional capabilities,generally controls the energizing of the electromagnet 64 and otheralarm or control features of the security system provided by theinvention. The lock control system 118 controls the energizing anddeenergizing of the electromagnet by selectively controlling the powertransmission to the electromagnet over lines 113. In one possibleembodiment of the invention, activation of switch 112 can activate anaudible and/or visible alarm 120 located in the housing 12. The alarmsignal generated directly can be at the location of the exit bar and/orcan be transmitted over lines 122 to a remote monitoring location toindicate that a door opening has been attempted. The lock control system118 and electromagnet 64 are powered over the multi-stranded cable thatcomprises the lines 122. In the preferred embodiment, the lock controlsystem 118 embodies a delay feature to delay deenergizing theelectromagnet 64 for a preestablished period of time after the switch112 has been activated.

For embodiments of the invention which employ a delay egress feature,the armature suspension bolt 76 does not rigidly fix the armature 70 tothe armature tray 74. With reference to FIGS. 1 and 3, the armature 70and an armature top plate 71 define armature cavity 124 therebetween.The armature bolt 76 and an armature spring 126 surrounding the armaturebolt 76 are located in the armature cavity 124. The armature spring 126exerts an expansion force between a bottom expanded washer like portionof armature bolt 76 and the armature top plate 71. The armature topplate 71 additionally defines a longitudinal slot 128 through which theupper portion of the armature bolt 76 passes. The upper portion of thearmature bolt 76 is rigidly fixed to armature tray 74. The configurationof the armature bolt assembly thus allows the armature tray 74 topartially lift away from the armature 70 even while the armature 70 isrigidly bonded to the energized electromagnet 64. As can be observed byreference to FIG. 8, the armature spring 126 is compressed between thearmature top plate 71 and the expanded portion of the armature bolt 76as the armature tray 74 is lifted away from the armature 70.

The armature tray 74 is initially limited in movement because theexpanded portion of the bolt 76 is greater in diameter than the width ofthe slot 128. This constrained movement allows, through thecorresponding actuation of the associated pins and links, for mainspring carrier 110 to move a sufficient distance longitudinally to aposition 110a to allow microswitch 112 to be activated and therebysignal the lock control system 118 (see FIG. 8). The slot 128, however,is relatively short in length so the armature tray 74 cannot move asufficient amount relative to the armature 70 to actually allow theretraction lever drive pad 56 to contact the latch retraction lever 58and to thereby retract latch 20.

Once the switch 112 has been activated, an interval timer of the lockcontrol system 118 counts down a preselected time before de-energizingelectromagnet 64. Should the switch 112 be constantly activated byspring carrier 110, the electronics 118 can signal to a remotemonitoring station 152 over lines 122 that the exit bar 10 is held orhas jammed in an open position thereby indicating a need for maintenanceor attention.

During periods of high traffic use, it may be advantageous to dog theexit bar 10 in an unlatched or released position. Dogging the latch 20reduces wear and tear on the latch mechanism and speeds ingress andegress through the doorway. When the dogging feature is selected, pushpad 30 is pushed inward to allow armature tray 74 to be in position 74b.The electromagnet may then be energized to hold the pad 30 and latch 20in a dogged or unlatched position. The push pad 30 remains retractedinto the housing while the latch 20 is dogged. The dogging feature maybe accomplished by a signal from the remote site over lines 122 incombination with a push force applied to the push pad 30. The lockcontrol system 118 can thus be instructed to dog the latch on the nextdoor opening. The lock control system 118 recognizes when the armatureis in partial contact with the attractive face and reenergizes theelectromagnet 64 to bond the armature. To implement remote dogging ofthe exit bar 10, a remote security system 152 transmits a doggingcommand signal to the lock control system 118. The lock control system118 deenergizes the electromagnet 64, which is normally maintained in anenergized state to lock the exit bar 10. The lock control system 118then waits for the retraction of the latch 20 and movement of thearmature 70 to the partial contact position to reenergize theelectromagnet 64. Preferably, the lock control system 118 waits untilreception of a signal from the switch 112 indicating pressure is beingapplied to the push pad, and therefore the armature 70 is in the partialcontact position with the electromagnet 64. Furthermore, the lockcontrol system 118 also monitors a latch position switch 156 to indicateretraction of the latch 20. The latch position switch 156 engages thelatch 20 in the released or unlatched position to generate a releasedsignal to the lock control system 118. The lock control system 118reenergizes the electromagnet 64 on reception of both signals.

The lock control system 118 further employs a fail safe system withregard to remote dogging of the latch 20. The signals generated from theswitch 112 and latch position switch 156 are preferably continuous.Interruption of the signals of either of the switches 112, 156, forexample, as a result of jamming of the mechanism or other unforeseenevent, causes the lock control system 118 to deenergize theelectromagnet 64. The deenergization of the electromagnet 64 oninterruption of either switch signal ensures releasability of the latch20 and passage through the doorway in an emergency situation. Therefore,the latch 20 cannot be inadvertently locked in the extended position bythe dogging signal.

With reference to FIG. 16, a key switch 153 at the door site 130, or akey switch 154 on an exit bar 10", may also be used to release andreenergize the electromagnet to allow dogging. Exit bar 10", which issimilar in form and function to the preferred embodiment pole magnetexit bar 10, further includes the key switch 154. The exit bars 10, 10'may each be undogged from a remote location by signalling lock controlsystem 118 to deenergize the electromagnet so as to allow the mainspring to reset the exit bar. Undogging can also be accomplished at thesite of the door by the key switch 154 or by the key switch 153 actingover lines 122.

The linkage system of the exit bar 10 of the invention has threediscrete internal positions to provide a delayed unlocking feature. Inthe first position, the armature 70 is in substantially full contactwith the energized electromagnet 64. (See FIG. 1.) This is the normallylocked position. Pushing on the push pad 30 or rotating the auxiliaryhandle 94 transforms the link system to a second position. In the secondposition (see FIG. 8), the armature 70 is still in full contact with theenergized electromagnet 64. The system has sufficient "play" or"flexibility" in the second position through the spring loaded armaturesuspension bolt 76, to allow the armature tray 74 to begin transverselifting away from the armature 70. This constrained transverse liftallows the switch 112 to be activated by the spring carrier 110 to begina delay sequence, activate an alarm, etc. The links, armature, armaturetray and other components are designated in the second position by an"a" following the numerical identifier 32a, 34a, 62a, 74a, 76a, 78a,86a, 110a and 126a.

As the link system moves the armature assembly, comprising the armaturetray 74 and armature 70, from the second to the third position of thelink system the electromagnet 64 is de-energized and the armature 70swings away from the electromagnet 64 to position 74b. (See FIG. 1.)When the link system is in the third position, the push pad 30 is pushedtransversely toward the door 14 or the handle 94 rotated, to actuate thelatch 20. The links, armature and other components are designated in thethird position by a "b" following the numerical identifier 32b, 70b,74b, 78b, 86b and 110b. The dogging feature is activated when the linksystem in the third position. The armature is held in partial contactwith the energized electromagnet 64 to maintain the latch 20 in anunlatched or released state.

With reference to a second embodiment of the invention employing asliding armature or shear lock configuration shown in FIGS. 9-15, theexit bar 10' has substantially the same structure, and operates insubstantially the same manner as that of the preferred embodiment exitbar 10 except for the differences and features described below.

The main lock frame 16' of the sliding armature embodiment of theinvention 10' is a generally longitudinal U-shaped channel with its openside oriented toward the door 14 to which the exit bar 10' is mounted.The frame 16' is held in the housing 12 in a spaced apart relation awayfrom a lower frame support 17 and the back panel 15 of the housing 12 byuse of an anchor block 108' and a bolt block 132. The frame 16' ismounted to the bolt block 132 and anchor block 108' by machine screws.The electromagnet 64 is mounted to the bottom of the channel of frame16' with the attractive face 72 of the electromagnet 64 oriented towardthe door 14.

The push pad 30 is pivotally mounted to master main link 32' and slavemain link 34', and operates in the same general manner as that of exitbar 10. The second link pins 48' and 52', however, are pivotally linkedto the armature tray 74'. Exerting a transverse force toward the door 14on the push pad 30, or rotating handle 94 to operate cam 98, results inlongitudinal displacement of the armature tray 74' toward the end of thehousing opposite the latch end.

A significant difference in construction between exit bar 10' and exitbar 10 is the arrangement, position and motion of the armature 70'. Thearmature 70' of the shear lock exit bar 10' is constructed to slideacross the attractive face 72 of the electromagnet 64, as compared tothe swinging arcuate motion of pole magnet exit bar 10.

Armature 70' is mounted to the armature tray 74' by armature posts 134.The armature posts 134 are secured to the armature tray by machinescrews 136. The armature posts 134 rest in recesses 137 located in theback of the armature 70', opposite the side of the armature 70'attracted to the electromagnet 64. The armature posts 134 fit into therecesses 137 of the armature 70' in such a manner as to allow thearmature 70' to move transversely to the face of the door while thearmature tray 74' remains fixed in the same transverse direction. Thearmature posts 134 do, however, resist shear motion in the longitudinaldirection along the axis of the exit bar. An armature leaf spring 138 issecured to the armature 70' by an armature spring screw 140. Thearmature spring 138 acts against the bottom of the armature posts 134 tohold the armature 70' in a spaced apart relation from the attractiveface 72 of the electromagnet 64 when the electromagnet 64 is notenergized.

With reference to FIG. 15, when the electromagnet 64 is energized,sufficient electromagnetic attractive force is created between theelectromagnet 64 and armature 70' to overcome the force of the armatureleaf spring 138 and move the armature 70' transversely toward theelectromagnet 64. This motion allows the armature 70' to obtain surfaceto surface contact with the attractive face 72, thereby locking the exitbar 10'. When armature 70' is attracted to electromagnet 64, armaturetray 74' is held in a fixed longitudinal position. Therefore, latchretraction is prevented by not permitting the lever drive pad 56 tocontact the latch retraction lever 58 to rotate latch 20.

Armature 70' further has two engagement slots 142 for receptiveengagement by lock dogs 144 which are mounted to frame 16'. Lock dogs144 extend transversely beyond the attractive face 72 of theelectromagnet 64. When armature 70' is held in electromagneticengagement with the electromagnet 64, lock dogs 144 extend intoengagement slots 142 which provide additional resistance to longitudinalshear forces generated by pressing the push pad 30 or rotating thehandle 94. The lock dogs 144 and engagement slots 142 help preventforced unlocking of the exit bar 10' by a large shear force generatedby, for example, a kick on the push pad 30.

The exit bar 10' can also be operated from the second side of the doorby a handle 94. The handle 94, by action of the spindle 96, operates thelock in much the same manner as in the preferred embodiment pole magnetexit bar 10. The cam 98, mounted to the spindle 96 directly contacts thearmature tray 74'. Therefore, when the handle 94 and spindle 96 rotate,the cam 98 drives the armature tray 74' longitudinally to activate thelatch 20 through the link system.

The sliding armature embodiment 10' may also be used in a delayed egressmode. In the delayed egress configuration, the armature 70' is heldinitially in a position closer to the latch end of the housing 12. Theelectromagnet 64 is energized and the armature 70' is drawn towards theattractive face 72. The armature 70' therefore rests upon the topsurfaces of the lock dogs 144. When the armature 70' is so positioned, agap exists between the armature 70' and the electromagnet 64 because thelock dogs 144 extend above the electromagnet attractive face 72. Thisgap between the armature 70' and attractive face 72 reduces theattractive force and allows the armature 70' to be displaced along thelongitudinal axis by a shear force even while the electromagnet 64 isenergized.

When the push pad 30 is pushed or the handle 94 is rotated, the actioncauses the armature 70' to translate along the longitudinal axis towardthe end of the exit bar opposite the latch. As the armature 70' moves inthis direction, the dogs 144 and the engagement slots 142 come intoalignment and the armature 70' is pulled by the energized electromagnetinto full surface to surface contact with the attractive face 72 of theelectromagnet 64. The contact between the armature 70' and electromagnet64 and the engagement of the lock dogs 144 in the slots 142 stop anyfurther longitudinal movement and provides a strong locking engagement.The longitudinal movement of the armature 70' from a position on top ofthe lock dogs 144 to where the lock dogs 144 engage the engagement slots142 is sufficient to allow the main spring carrier 110 to movesufficiently longitudinally to actuate the microswitch 112. (See FIG.15.) The switch actuation signals the lock control system 118 to begincounting the preestablished delayed unlock time interval.

When the armature 70' is in full bonded engagement with the attractiveface 72 and the dogs 144 are positioned in the engagement slots 142, thearmature tray 74' is highly resistant to movement in the longitudinaldirection. When the lock control system 118 deenergizes theelectromagnet 64, the armature spring 138 retracts the armature 70' fromthe lock dogs 144. The armature 70' can then be moved longitudinallytoward the end of the exit bar opposite the latch wherein additionalpushing on the push pad 30 or rotation of the handle 94 allows the latch20 to be retracted or released from the strike 24.

The sliding armature embodiment 10' may also be used to dog the latch 20so as to reduce wear of components and allow easier ingress and egressthrough the doorway. The dogging is accomplished by transverselydepressing the push pad 30 to move the armature 70' to the maximumdisplaced position 70'b toward the end of the exit bar opposite thelatch end. Next, the magnet 64 is energized by a key switch 154 or froma remote monitoring station 152. The armature 70' will bond to theelectromagnet 64, preventing the link system from returning to theinitial position of the system. In the dogged position of the armature70'b, the lock dogs 144 are not engaged into the engagement slots 142and the armature tray 74' is held in a fixed longitudinal position dueto the frictional engagement between the armature 70' and the topsurface of the lock dogs 144 in combination with the electromagneticattraction.

Similar to the preferred embodiment of the exit bar 10, the slidingarmature exit bar 10' also operates in a three position sequence for thearmature/link system for a delayed unlocking application. In the firstposition, the armature 70' is held in an initial position by theenergized electromagnet 64 wherein the armature 70' rests on top of theends of the lock dogs 144. A gap therefore exists between the attractiveface 72 of the electromagnet 64 and the armature 70'. Rotation of thehandle 94 or pushing of the push pad 30 moves the armature 70' along thelongitudinal axis to a position 70'a where the armature 70' is in fullsurface to surface contact with the attractive face 72 of theelectromagnet 64.

In the second position, the lock dogs 144 are positioned in theengagement slots 142 of the armature 70'. Also, in this second position,the switch 112 is actuated and signals the lock control system 118 tobegin the delay sequence. The push pad 30 cannot move inwardlysufficiently far to actuate the latch 20 when the armature 70' is in thesecond position. The links and other components are designated in thesecond position by an "a" following the numerical identifier, e.g.,32'a, 34'a, 70'a, 110a.

When the electromagnet 64 is deenergized, the armature 70' can be movedto a third position. In the third position, the push pad 30 can bepushed sufficiently far transversely toward the door face, or the handle94 rotated sufficiently far, to actuate the latch 20. The links,armature 70' and other components are designated in the third positionby a "b" following the numerical identifier, 32'b, 34'b, 70'b, 110'b.

In a manner similar to that of the preferred embodiment, dogging isimplemented by energizing the electromagnet 64 when the link system isin the third position thereby maintaining the push pad 30 in a positionrecessed into the housing 12 while the latch 20 is released orretracted.

With reference in particular to FIG. 16, the exit bar 10" is mounted toa door 14 supported in a door frame 26. The exit bar 10" is preferablysupplied with electricity from a remote power supply 150 over lines 122in a conventional manner.

The exit bars of the invention are readily adaptable for communicationwith a remote security system 152. The remote security system 152, whichmay also incorporate fire safety features, can be used to securely lockor unlock the exit bar and receive alarm information with regard toattempted egress or ingress through the doorway. The remote system canfurther control dogging or undogging of the exit bar. The exit bars ofthe invention can also be integrated into a complete security systemwherein exit through the doorway without activation of an alarm can onlybe accomplished by use of a valid input in an electronic access device160, such as a card reader or touch pad, at the location of the doorway.An additional electronic reader device 161 can be provided at the secondside or exterior of the door 14 for the same purpose.

The lock control system 118 has a microprocessor 162 that allows for onboard programmable access control by defining a plurality of possibleoperating parameters which are specifically selected for a givenapplication. (See FIG. 17) An example of a door lock having on boardprogrammable access control is disclosed in U.S. Pat. No. 5,479,151,issued Dec. 26, 1995 to Lavelle et al, which is hereby incorporated byreference. The microprocessor 162 of the lock control system 118 ispreferably capable of supporting a wide range of on board programming,audit trail storage and retrieval, and multiple electronic accessdevices.

The microprocessor 162 preferably has an associated real time clock andaudit trail recorder 164. An example of a door security system audittrail is described in U.S. patent application Ser. No. 08/384,771 filedFeb. 7, 1995 by Lavelle et al which is hereby incorporated by reference.The audit trail recorder 164 records the user access number and the timeand date of the use of the exit bar 10. The recorded audit trailinformation can be downloaded to a portable programming and retrievaldevice such as a computer, or downloaded to the remote security system152. The audit trail recorder 164 can further record other lock events.Such other events may include recording when the last audit trailinformation was downloaded, recording when the exit bar 10 is initiallypowered up, recording release of the exit bar 10 due to a fire alarm,recording invalid user attempts when the user has been deleted from theprestored access codes, recording when the secured door 14 is forcedopen, and other lock events.

The microprocessor 162 has an associated erasable non-volatile memory166. The non-volatile memory 166 contains user access code data and datawhich electronically defines applicable options and features of the exitbar 10. The microprocessor 162 compares user access codes entered at theelectronic access devices 160, 161 to user access codes stored in thenon-volatile memory 166. A valid comparison allows immediate release ofthe exit bar 10 and/or actuation of the auxiliary handle 94 to allowentry through the secured door 14.

The microprocessor 162 preferably receives user access codes throughmultiple electronic access devices 160, 161 including keypads andcontact activatable reader devices 168. An example of a multiple accesselectronic lock system includes U.S. patent application Ser. No.08/577,267, Multiple Access Electronic Lock System, filed Dec. 22, 1995,by Lavelle et al, which is herein incorporated by reference. Multiple,overlapping electronic access devices 160, 161, 168, communicating withthe microprocessor 162 through an access control interface 170, allowselective release of the exit bar 10. The exit bar 10 preferably hasmultiple electronic access devices 160, 161, 168 positioned on at leastone side of the doorway. One electronic access device is preferably akeypad for receiving a personal access code. The second electronicaccess device is an electronic "key" reader, such as a card reader, acontact activatable reader device 168 or computer data port forreceiving electronic access codes. The lock control system 118 isresponsive to either entry of a personal access code or an electronicaccess code. The lock control system 118 can be further configured torequire both forms of access codes in order to release the latch 20.

The microprocessor 162 can further control access from the secondary orexterior side of the door 14 by directly controlling actuation of theauxiliary handle 94. The auxiliary handle 94 can be additionally securedby a motor driven or solenoid driven locking mechanism in addition to orinstead of employing the electromagnet 64 and armature 70 for locking ofthe auxiliary handle 94. A solenoid or electric motor selectivelyrotatably fixes the auxiliary handle 94 to prevent actuation of thelatch 20. The microprocessor 162 can control the solenoid via a solenoiddriver 172 or the electric motor via an electric motor driver 174 toselectively release the auxiliary handle 94. Operation of the solenoidor electric motor through the solenoid driver 172 and electric motordriver 174 therefore further controls access through the door 14.

The microprocessor 162 receives status signals from lock status switches178 to determine the status of the exit bar. Status signals can begenerated by lock status switches 178 including the initial motionswitch (IMS) 112, the latch position switch (LPS) 176, a magnetic bondsensor (MBS) 177, a trim position switch (TPS) 179, or an anti-tamperswitch (ATS) 181. The magnetic bond sensor 177 senses whether there issufficient magnetic holding force between the electromagnet 64 and thearmature 70 to ensure adequate locking of the exit bar 10. The magneticbond sensor 177 is responsive to low line voltage and/or foreignmaterial in the magnetic gap between the electromagnet 64 and thearmature 70, and/or dirty or damaged surfaces on the electromagnet 64 orthe armature 70. The anti-tamper switch 181 can signal removal of themain housing 12 from the exit bar 10. The trim position switch 181monitors the rotational position of the auxiliary handle 94. Themicroprocessor 162 employs the lock status switches 178 including theIMS 112, LPS 176, MBS 177, TPS 179 and ATS 181 switches to continuallymonitor lock status. The lock status received by the lock control system188 can be transmitted to the remote security system 152, recorded inthe audit trail recording 164, or initiate a response at the exit bar 10such as sounding the alarm 120.

Programming of the microprocessor 162 is partially accomplished via modeselection switches 182. The mode selection switches 182 allow fieldselection of the operational parameters of the microprocessor 162. Theseparameters include the amount of timing delay for the delayed egressfunction of the exit bar 10. Furthermore, the mode selection switches182 can select a relay output 180 having a usable configurable form Coutput to signal an alarm condition or bar secure status.

A fire alarm 184, acting through a fire alarm interface 186 and anoptical isolation interface 188, can initiate in immediatedeenergization of the electromagnet coil 68. Additional external inputs190, including dogging signals and other command or control signals fromthe remote security system 152, are transmitted through a networkcommunications interface 192 and the optical isolation interface 188 tocontrol and program the microprocessor 162. A serial test andconfiguration port 194 is further provided to test the exit bar andreceive outputs from the microprocessor 162 for diagnostic purposes. Themicroprocessor 162 also controls the audible alarm 120 and the visiblealarm or indicators 121. The visible indicators 121 can include lightemitting diodes mounted to the exit bar to indicate lock or alarmstatus.

In a further embodiment of the invention, a network or communicationsystem 196 provides an interconnected communication control for aplurality of exit bars 10 securing a plurality of doors 14. (See FIG.18) The communication system 196 is preferably employed for a pair ofdoors 14 or a bank of doors 14 that generally require simultaneouscontrol. The communication system 196 can also be employed with a singleexit bar 10. The communication system 196 is preferably operationallypositioned between the remote security system 152 and the lock controlsystems 118 of the exit bars 10. The communication system 196 thereforepreferably receives lock command signals from the remote security system152 and controls the exit bars in response to the command signals.Furthermore, the communication system monitors the status of the exitbars 10 and controls the exit bars in response to the monitoring. Thecommunication system 198 preferably further transmits the status of theexit bar to the remote security system 152.

The communication system 196 has a communication controller 198. Thecommunication controller 198 is in constant communication with each ofthe exit bars 10 and controls the exit bars 10 to function in unison asa single entranceway or opening. The communication controller 198 isconstructed of a printed circuit card mountable in a separate enclosureor integrated into the power supply 150. The communication controller198 has a microprocessor 200, preferably a Motorola MC68HC705J1A, whichperforms all communication and logic functions. (See FIG. 19) Themicroprocessor 200 is electrically connected to the exit bars 10 via anintegrated circuit driver/receiver for the transmission of commandsignals to the exit bars 10, and reception of lock status signals fromthe exit bars 10. The driver/receiver 202 is preferably an RS485conforming to the EIA-485 industry standard. The microprocessor 200 issupported by an oscillator 204 and a power on reset circuit 206. Statusindicators 208, preferably light emitting diodes, indicate the operatingcondition of the communication controller 198.

A remote release 210, remote reset 212, time zone 214 and dogging 216inputs are connected to the microprocessor 200 via an optically isolatedinput buffer 218. Additional inputs 220 can be directed through theinput buffer 218 for the microprocessor 200. The inputs 210, 212, 214,216, 220 are preferably controlled and initiated by the remote securitysystem 152.

To reduce the required wiring, the fire alarm 184 is preferably directedthrough the communication controller instead of individually wired toeach exit bar 10. The fire alarm 184 is optically isolated from themicroprocessor 200 by the input buffer 218. The fire alarm 184 furtheroperates a fire alarm relay 222 to deenergize the exit bars 10 forimmediate release during a fire or emergency. The outputs of themicroprocessor 200 are isolated with relays 224, 226 powered by an onboard 12 volt regulator and driven through a driver IC. The relay statusoutputs of the relays 224, 226 indicate lock status and alarm status forthe communication system 196. The communication controller 198 furthercontrols an alarm 234.

A control wire 228 preferably having four conductors or wires connectsthe communication controller 198 to each of the exit bars 10. Thecontrol wire 228 is formed of two power wires 230 and two communicationwires 232. In the preferred embodiment, the control wire 228 networksthe exit bars 10 and the communication controller 198 wherein only asingle control wire 228 is required. The communication controller 198therefore broadcasts to and receives signals from all the exit bars 10over the same control wire 128.

The communication controller 198 performs a configuration process toassign a unique address to each exit bar 10 during the installationprocedure for the communication system 196. The address assigned to eachbar is used in the polling operation to avoid data collisions. Each exitbar 10 may respond to the communication system 196 only when polled bythe communication controller 198 with the correct unique address.Furthermore, the lock control system 118 of each exit bar 10 reads allcommand signals of the communication controller 198 to determine if thecommand signal is directed to that particular exit bar 10.

Configuration of the communication system 196 is accomplished bypressing a push button 236 on the communication controller 198. Thecommunication controller 198 then broadcasts a command signal to thelock control system 118 of each exit bar 10 to enter a configurationmode. The installer of the communication system 196 then presses thepush pad on each exit bar 10 to close the switch 112. When the switch112 is closed on an exit bar 10, the lock control system 118 of thatexit bar 10 sends an acknowledged signal to the communication controller198. The communication controller 198 receives the acknowledge signalfrom the exit bar 10 and responds with a configuration command to theparticular lock control system 118 which contains the address to beassigned to that particular exit bar 10. This address is stored by thelock control system 118 in the non-volatile memory 166. The address isused by the lock control system 118 for all subsequent pollingfunctions. During operation of the communication network 196, thecommunication controller 198 preferably only polls the number of exitbars 10 attached to the communication system 196 to maintain the fastestresponse time.

The command, polling, acknowledge and other signals transmitted betweenthe communication controller 198 and the exit bars 10 are preferably ofa 2 or 3 byte format. The last byte is always an 8 bit cyclic redundancycheck (CRC) data error detection system. The first byte is the commandor process byte instructing the exit bar 10 the function to perform. Forexample, the communication controller 198 will transmit a two byte pollcommand to the exit bars 10. The first or command byte contains both thepoll command and the address of the exit bar 10 to which the command isdirected. Therefore, every exit bar 10 checks the first byte todetermine if the signal is directed to that particular exit bar. Thesecond byte of the poll command is the CRC error detection system.

The intermediate byte or data byte is only employed when particular datais required to perform the command contained in of the command byte. Forexample, the broadcast command is a three byte message with thebroadcast instruction in the first byte. The data broadcast is containedin the second byte, and the third byte is again the CRC error detectionsystem.

The communication controller 198, upon power up and periodically undernormal operation, polls the maximum number of exit bars 10 andreconfigures itself to that number of subsequent polls. In oneembodiment of the communication network 196, the communicationcontroller 198 can poll up to a maximum number of 32 exit bars.

With reference to FIG. 20, showing the flow chart for the pollingroutine for the communication controller 198, the communicationcontroller 198 performs an initialization step 238 after startup. Thecommunication controller 198 then performs a read inputs step 240. Thecommunication controller 198 reads the inputs that include the remoterelease input 210, the remote reset input 212, the remote time zoneinput 214, the remote dogging input 216 and any additional inputs 220.The communication controller 198 then broadcasts at step 242 anyrequired commands to the exit bars 10 as a result of the read inputsstep 240.

The communication controller 198 next sets a register N to 0 at step 244and polls the first exit bar at step 246. The register N counts the exitbars 10 serviced by the communication system 196. Each exit bar 10responds with an acknowledge signal received by the communicationcontroller at step 248 whereafter the communication controller 198 testsfor responses at step 250. If a response is received from the exit bar10, the communication controller 198 broadcasts a command at step 252 tocause all of the exit bars to function in unison as a single opening.

For example, if the returned acknowledge signal from an exit bar 10indicated that an unauthorized egress attempt was in progress, thecommunication controller 198 transmits a broadcast command to all theexit bars 10 in the communication network 196 to begin the delay egressalarm. All the exit bars 10 will receive the command preferablygenerally simultaneously and enter the alarm condition. Thus, at theconclusion of the egress delay time, all the exit bars 10 will unlock inconcert. After broadcasting at step 252 or receiving no acknowledgedresponse at step 250, the communication controller 198 adds one to theregister at step 254 and determines if the last exit bar is being polledat step 256. The communication controller 198 continues to poll the exitbars connected to the communication system 196 until the last exit barhas been polled, and then returns to the read input function at step240.

The communication controller 198 can broadcast several commands to theexit bars 10. These include a delay egress alarm, inner configurationmode, release, reset, dog the latch, door status monitor and day/nightcommands to change the access parameters stored in the non-volatilememory of the lock control system 118. The broadcast of a command signalby the communication controller 198 can be initiated by either a pollresponse from an exit bar 10, or a command signal from the remotesecurity system 152. The communication controller can further poll eachexit bar 10 in turn for an acknowledge signal that includes the exit barstatus secured, alarm activated, anti-tamper switch activated and doorstatus monitor activated. Furthermore, the communication controller cansignal the exit bar for the configuration sequence described above. Itshould be recognized that the communication system 196 is readilyadaptable to control a plurality of exit devices including exit bars,but also can control other forms of electrically controlled exit devicesincluding electrically controlled cylinder locks, mortise locks,electromagnetic locks and electric strikes.

While a preferred embodiment of the foregoing invention has been setforth for purposes of illustration, the foregoing description should notbe deemed a limitation of the invention herein. Accordingly, variousmodifications, adaptations and alternatives may occur to one skilled inthe art without departing from the spirit and the scope of the presentinvention.

What is claimed is:
 1. An exit bar for mounting to a door face, saidexit bar comprising:a housing adapted for mounting to a door face; apush pad mounted to said housing, said push pad defining an exposed pushface for receiving a push force; latch means extending from said housingfor releasably latching a door; link means for linking said pad to saidlatch means to release said latch means when said pad is pushed; lockmeans disposed in said housing for locking said link means, said lockmeans comprising electromagnet means and armature means forelectromagnetic bonding to said electromagnet means to lock said linkmeans; and programmable controller means within said housing foractuating said lock means.
 2. The exit bar of claim 1 further comprisinghandle means mountable on a second face of said door for releasing saidlatch means.
 3. The exit bar of claim 1 wherein said lock means istransformable between a locked and an unlocked state and furthercomprising delay means for delaying transforming said lock means to anunlocked state for a preestablished delay time interval after said padis pushed.
 4. The exit bar of claim 3 wherein said delay means comprisesswitch means activated by said link means to begin said delay timeinterval.
 5. The exit bar of claim 1 wherein said link means furthercomprises a yieldable armature bolt means connecting said armature meansand said link means.
 6. The exit bar of claim 4 wherein saidelectromagnet means and said armature means electromagnetically bond tosupport said latch means in a dogged position.
 7. The exit bar of claim1 wherein said electromagnet means and said armature meanselectromagnetically bond to support said latch means in a doggedposition.
 8. The exit bar of claim 1 further comprising:first readermeans for generating user access codes; and wherein said controllermeans includes storage means for storing at least one user access code,said controller means responsive to said first reader means forcomparing said user access codes to stored user access codes, andautomatically actuating said lock means in response to said comparison.9. The exit bar of claim 8 further comprising second reader means forgenerating user access codes and said controller means responsive tosaid second reader means for comparing said user access codes of saidsecond reader means to stored user access codes, and automaticallyactuating said lock means in response to said comparison.
 10. The exitbar of claim 9 wherein said first reader means is a keypad and saidsecond reader means is for reading an electronic key.
 11. The exit barof claim 8 wherein said controller means is programmable to add andremove stored user access codes.
 12. The exit bar of claim 8 whereinsaid controller means further comprises audit trail means for storingsaid user access codes and storing time information indicative of thetime said user access codes were received by said input means.
 13. Thedoor security system of claim 12 wherein said controller means furthercomprises downloading means for transferring said stored user accesscodes and stored time information to a computer.
 14. The exit bar ofclaim 8 wherein said controller means further comprises storage means tostore variable access states corresponding to prestored access codes andreal time means for selectively controlling said lock means as afunction of real time.
 15. The exit bar of claim 12 wherein saidcontroller means is programmable to add and remove stored user accesscodes.
 16. An exit bar for mounting to a door face comprising:a housingadapted for mounting to a door face; a push pad mounted to said housing,said push pad defining a push face for receiving a push force; latchmeans extending from said housing for releasably latching a door; linkmeans for linking said pad to said latch means so as to release saidlatch means when said pad is pushed; electromagnetic lock means disposedin said housing for electromagnetically locking said link means and fordogging said latch means in a released position, said lock meanscomprising an electromagnet; and programmable control means mounted tosaid housing for controlling said lock means.
 17. The exit bar of claim16 wherein said control means controls energizing and de-energizing ofsaid electromagnet.
 18. The exit bar of claim 16 wherein saidelectromagnetic lock means further comprises an armature forelectromagnetic bonding to said electromagnet.
 19. The exit bar of claim18 wherein said link means are connected to said armature, and whereinsaid link means hold said armature in a first position when said linkmeans is locked, and hold said armature in a second position when saidlatch means is released.
 20. The exit bar of claim 19 wherein saidelectromagnet lock means dog said latch means by energizing saidelectromagnet when said armature is in said second position.
 21. Theexit bar of claim 16 comprising delay means for delaying releasing saidlatch means for a pre-established time interval after said push pad ispushed.
 22. The exit bar of claim 21 wherein the delay means comprisesswitch means activated by said link means to begin said pre-establishedtime interval.
 23. The exit bar of claim 17 further comprising switchmeans for generating a latch signal indicative of said latch means inthe released position and remote dogging means for transmitting adogging signal to said control means, said control means deenergizingsaid electromagnet when said dogging signal is received and reenergizingsaid electromagnet when said latch signal is subsequently received tothereby dog said latch means.
 24. The exit bar of claim 17 furthercomprising initial motion switch means for transmitting a motion signalto said control means indicating pressure on said push pad;latchposition switch means for transmitting a latch signal to said controlmeans indicating said latch means in said released position; and remotedogging means for remotely dogging said latch means, said dogging meanstransmitting a dogging signal to said control means and said controlmeans deenergizing said electromagnet when receiving said dogging signaland subsequently energizing said electromagnet after subsequentlyreceiving said latch signal and said motion signal.
 25. The exit bar ofclaim 24 wherein said latch signal and said motion signal are generallycontinuous, and said control means deenergizes said electromagnet toreturn said latch means to said latched position when one of said latchsignals and motion signals is interrupted.
 26. An exit bar for securinga door, said bar comprisinga housing adapted for mounting to a doorface; a push pad mounted to said housing, said push pad defining a pushface for receiving a push force; latch means extending from said housingfor releasably latching a door; link means for linking said push pad tosaid latch means wherein when said push pad is pushed, said latchreleases; lock means for locking said link means, said lock meanscomprising an electromagnet means and an armature means for bonding tosaid electromagnet means; switch means for generating a signal when saidpush pad is pushed, said link means supporting said armature means in afirst position wherein said link means is locked when said electromagnetmeans is energized, said armature means being movable to a secondposition when a push force is exerted against said push pad, said switchmeans generating a signal at said second position and said link meansbeing locked when said electromagnet is energized at said secondposition and said armature means being movable to a third positionwherein said latch means is released; and a lock programmable controlsystem enclosed within said housing and operably connected to said lockmeans.
 27. The exit bar of claim 26 wherein said latch means is doggedby energizing said electromagnet means when said link means supportssaid armature means in said third position.
 28. The exit bar of claim 26further comprising a delay means for delaying releasing said latch meansfor a preestablished time interval after said signal is generated. 29.The exit bar of claim 26 wherein said armature means contacts saidelectromagnet means in said first and said second positions.
 30. Theexit bar of claim 26 further comprising main spring means for biasingsaid link means to supporting said armature means in said firstposition.
 31. A door security system comprising:an electricallycontrolled exit device having a plurality of lock states and containinga programmable lock controller means for operating said exit device andgenerating a lock status signal indicative of said lock state inresponse to a polling signal; communication controller meanselectrically connected to said exit device for transmitting a pollingsignal to said exit device and receiving said lock status signals, saidcommunication controller means further comprising command means forreceiving lock commands from a remote security system and broadcastingsaid lock commands to said lock controller, said lock controllercontrolling said exit device in response to said lock commands.
 32. Thedoor security system of claim 31 comprising a plurality of electricallycontrolled exit devices, each said exit device having a plurality oflock states and containing said programmable lock controller means, saidcommunication controller means electrically connected to each said exitdevice for transmitting said polling signal to each said exit device,receiving said lock status signals from said exit devices andcontrolling said exit devices in response to said lock commands.
 33. Thedoor security system of claim 32 wherein said exit devices areelectromagnetically secured exit bars.
 34. The door security system ofclaim 32 wherein said communication controller means controls said exitdevices in unison.
 35. The door security system of claim 34 wherein saidexit devices are electromagnetically secured exit bars.
 36. The doorsecurity system of claim 32 wherein each said exit device has a uniqueaddress, and said communication controller means assigns said address toeach said exit devices.
 37. The door security system of claim 36 whereinsaid communication controller means controls said exit devices inunison.
 38. The door security system of claim 32 wherein saidcommunication controller controls said plurality of exit devices inresponse to a polled lock status signal of one of said lock controllermeans.
 39. The door security system of claim 38 wherein saidcommunication controller controls said exit devices in unison.
 40. Thedoor security system of claim 32 wherein said one of said exit devicestransmits a lock status signal indicative of an unauthorized egress andsaid communication controller controls said plurality of exit devices tooperate in unison after a predetermined delay time.
 41. The doorsecurity system of claim 31 further comprising reader means forgenerating user access codes and said lock controller means includesstorage means for storing at least one user access code and isresponsive to said reader means for comparing said user access codes tostored access codes and automatically operating said exit device inresponse to said comparison.
 42. The door security system of claim 32further comprising a plurality of reader means for generating useraccess codes, one of said reader means associated with each said exitdevice, said controller means responsive to said associated reader meansfor comparing said user access codes to stored access codesautomatically operating said exit device in response to said comparison.